Two senior Coalition MPs are expected to use Parliament's final sitting day of the year to announce their retirement, joining a growing number of federal politicians who will not recontest their seats at the next election.
Former attorney-general Christian Porter announced via social media on Wednesday afternoon, he would not return to Parliament House after the next election.
The West Australian MP's retirement came amid speculation a senior minister, Greg Hunt, was planning to announce his exit from politics this week.
Mr Porter, who has strenuously denied historical rape allegations made against him after a Four Corners investigation was released earlier this year, said he had "no regrets" about his time in politics.
His decision would allow him to spend more time with "those around me whose love has been unconditional" after weeks of speculation about his possible exit from politics.
Mr Porter used his statement to take a swipe at critics he claimed had made the allegations about him.
"Perhaps the only certainty now is that there appears to be no limit to what some will say or allege or do to gain an advantage over a perceived enemy," he said.
"This makes the harshness that can accompany the privilege of representing people, harder than ever before. But even though I have experienced perhaps more of the harshness of modern politics than most, there are no regrets."
Ms Milligan was the author of an online article in February which revealed an unnamed cabinet minister was the subject a historic rape allegation.
Days later, a tearful Mr Porter outed himself as the accused minister. The then attorney-general rejected the allegations.
His decision to launch defamation action against the ABC prompted him to resign as the nation's first law officer.
Parliament's privileges committee this week cleared Mr Porter over his blind trust, but recommended the rules be updated.
Rumours also swirled on Wednesday suggesting senior Liberal minister Greg Hunt would announce his retirement from parliament, 20 years after he was first elected.
Speculation has surrounded the Health Minister's future for months but he has previously shied away from claims he would be stepping away from politics.
ABC Insiders host David Speers asked Mr Hunt of whether he still planned to contest his Mornington Peninsula seat at the next election, likely to be set for March or May next year.
He responded briefly that he was "pre-selected and running" for the 2022 election.
Treasurer Josh Frydenberg didn't confirm the rumours on Wednesday while announcing the third-quarter GDP figures, preferring to wait for public comments to be made by his "dear friend".
"Greg is my closest friend in this place," he said.
"The godfather to his beautiful daughter Poppy, and he is the godfather to my daughter.
"The fact that Australia has one of the lowest mortality rates in the world, and the fact that we have one of the highest vaccination rates in the world is due in no small part to the incredible work that all health professionals have done across Australia.
"Greg as the Health Minister in this once-in-a-century pandemic has been outstanding."
Labor's shadow treasurer Jim Chalmers also wished him well despite not always supporting his decisions as a minister.
"If he is resigning, I'm sure his family is looking forward to seeing more of him," Dr Chalmers said.
"I'm sure he's done his best. I'm sure he's put a lot of effort and a lot of time into that.
"And so if he is resigning, on a personal note, I wish him well."
The two politicians will join six Labor MPs - Sharon Bird, Julie Owens, Warren Snowdon, Joel Fitzgibbon, Nick Champion and Chris Hayes - and seven Coalition MPs - Kevin Andrews, Ken O'Dowd, Nicolle Flint, Andrew Laming, John Alexander, Steve Irons and George Christensen - who have confirmed they will not contest for the 47th Parliament's lower house.
The final day of sitting is expected to be a wild card with the days the federal government can introduce and pass legislation being numbered.
A controversial voter identification bill has reportedly been dropped as part of a bipartisan deal with Labor.